Electric field dependence of microwave losses in strontium titanate

Electric field dependent microwave losses in pure single strontium titanate crystal have been theoretically calculated at microwave frequency 5 GHz. T he loss tangent consists of a contribution, which is quadratic in applied b iasing plus a field independent contribution. This variation of tan delta w ith applied field is noticeable in the vicinity of the Curie temperature. I n the high temperature region, the field's effect ceases and the increase i n loss arises mainly due to higher order anharmonic terms.